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v3.15
 
   1/*
   2 * platform.c - platform 'pseudo' bus for legacy devices
   3 *
   4 * Copyright (c) 2002-3 Patrick Mochel
   5 * Copyright (c) 2002-3 Open Source Development Labs
   6 *
   7 * This file is released under the GPLv2
   8 *
   9 * Please see Documentation/driver-model/platform.txt for more
  10 * information.
  11 */
  12
  13#include <linux/string.h>
  14#include <linux/platform_device.h>
  15#include <linux/of_device.h>
  16#include <linux/of_irq.h>
  17#include <linux/module.h>
  18#include <linux/init.h>
 
 
  19#include <linux/dma-mapping.h>
  20#include <linux/bootmem.h>
  21#include <linux/err.h>
  22#include <linux/slab.h>
  23#include <linux/pm_runtime.h>
 
  24#include <linux/idr.h>
  25#include <linux/acpi.h>
 
 
 
 
 
 
 
  26
  27#include "base.h"
  28#include "power/power.h"
  29
  30/* For automatically allocated device IDs */
  31static DEFINE_IDA(platform_devid_ida);
  32
  33struct device platform_bus = {
  34	.init_name	= "platform",
  35};
  36EXPORT_SYMBOL_GPL(platform_bus);
  37
  38/**
  39 * arch_setup_pdev_archdata - Allow manipulation of archdata before its used
  40 * @pdev: platform device
  41 *
  42 * This is called before platform_device_add() such that any pdev_archdata may
  43 * be setup before the platform_notifier is called.  So if a user needs to
  44 * manipulate any relevant information in the pdev_archdata they can do:
  45 *
  46 *	platform_device_alloc()
  47 *	... manipulate ...
  48 *	platform_device_add()
  49 *
  50 * And if they don't care they can just call platform_device_register() and
  51 * everything will just work out.
  52 */
  53void __weak arch_setup_pdev_archdata(struct platform_device *pdev)
  54{
  55}
  56
  57/**
  58 * platform_get_resource - get a resource for a device
  59 * @dev: platform device
  60 * @type: resource type
  61 * @num: resource index
 
 
  62 */
  63struct resource *platform_get_resource(struct platform_device *dev,
  64				       unsigned int type, unsigned int num)
  65{
  66	int i;
  67
  68	for (i = 0; i < dev->num_resources; i++) {
  69		struct resource *r = &dev->resource[i];
  70
  71		if (type == resource_type(r) && num-- == 0)
  72			return r;
  73	}
  74	return NULL;
  75}
  76EXPORT_SYMBOL_GPL(platform_get_resource);
  77
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  78/**
  79 * platform_get_irq - get an IRQ for a device
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  80 * @dev: platform device
  81 * @num: IRQ number index
 
 
 
 
 
 
 
 
 
 
 
 
 
  82 */
  83int platform_get_irq(struct platform_device *dev, unsigned int num)
  84{
 
  85#ifdef CONFIG_SPARC
  86	/* sparc does not have irqs represented as IORESOURCE_IRQ resources */
  87	if (!dev || num >= dev->archdata.num_irqs)
  88		return -ENXIO;
  89	return dev->archdata.irqs[num];
 
  90#else
  91	struct resource *r;
  92	if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node)
  93		return of_irq_get(dev->dev.of_node, num);
 
 
 
 
  94
  95	r = platform_get_resource(dev, IORESOURCE_IRQ, num);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  96
  97	return r ? r->start : -ENXIO;
  98#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  99}
 100EXPORT_SYMBOL_GPL(platform_get_irq);
 101
 102/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 103 * platform_get_resource_byname - get a resource for a device by name
 104 * @dev: platform device
 105 * @type: resource type
 106 * @name: resource name
 107 */
 108struct resource *platform_get_resource_byname(struct platform_device *dev,
 109					      unsigned int type,
 110					      const char *name)
 111{
 112	int i;
 113
 114	for (i = 0; i < dev->num_resources; i++) {
 115		struct resource *r = &dev->resource[i];
 116
 117		if (unlikely(!r->name))
 118			continue;
 119
 120		if (type == resource_type(r) && !strcmp(r->name, name))
 121			return r;
 122	}
 123	return NULL;
 124}
 125EXPORT_SYMBOL_GPL(platform_get_resource_byname);
 126
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 127/**
 128 * platform_get_irq_byname - get an IRQ for a device by name
 129 * @dev: platform device
 130 * @name: IRQ name
 
 
 
 
 131 */
 132int platform_get_irq_byname(struct platform_device *dev, const char *name)
 133{
 134	struct resource *r = platform_get_resource_byname(dev, IORESOURCE_IRQ,
 135							  name);
 136
 137	return r ? r->start : -ENXIO;
 
 
 
 
 138}
 139EXPORT_SYMBOL_GPL(platform_get_irq_byname);
 140
 141/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 142 * platform_add_devices - add a numbers of platform devices
 143 * @devs: array of platform devices to add
 144 * @num: number of platform devices in array
 145 */
 146int platform_add_devices(struct platform_device **devs, int num)
 147{
 148	int i, ret = 0;
 149
 150	for (i = 0; i < num; i++) {
 151		ret = platform_device_register(devs[i]);
 152		if (ret) {
 153			while (--i >= 0)
 154				platform_device_unregister(devs[i]);
 155			break;
 156		}
 157	}
 158
 159	return ret;
 160}
 161EXPORT_SYMBOL_GPL(platform_add_devices);
 162
 163struct platform_object {
 164	struct platform_device pdev;
 165	char name[1];
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 166};
 167
 168/**
 169 * platform_device_put - destroy a platform device
 170 * @pdev: platform device to free
 171 *
 172 * Free all memory associated with a platform device.  This function must
 173 * _only_ be externally called in error cases.  All other usage is a bug.
 174 */
 175void platform_device_put(struct platform_device *pdev)
 176{
 177	if (pdev)
 178		put_device(&pdev->dev);
 179}
 180EXPORT_SYMBOL_GPL(platform_device_put);
 181
 182static void platform_device_release(struct device *dev)
 183{
 184	struct platform_object *pa = container_of(dev, struct platform_object,
 185						  pdev.dev);
 186
 187	of_device_node_put(&pa->pdev.dev);
 188	kfree(pa->pdev.dev.platform_data);
 189	kfree(pa->pdev.mfd_cell);
 190	kfree(pa->pdev.resource);
 
 191	kfree(pa);
 192}
 193
 194/**
 195 * platform_device_alloc - create a platform device
 196 * @name: base name of the device we're adding
 197 * @id: instance id
 198 *
 199 * Create a platform device object which can have other objects attached
 200 * to it, and which will have attached objects freed when it is released.
 201 */
 202struct platform_device *platform_device_alloc(const char *name, int id)
 203{
 204	struct platform_object *pa;
 205
 206	pa = kzalloc(sizeof(struct platform_object) + strlen(name), GFP_KERNEL);
 207	if (pa) {
 208		strcpy(pa->name, name);
 209		pa->pdev.name = pa->name;
 210		pa->pdev.id = id;
 211		device_initialize(&pa->pdev.dev);
 212		pa->pdev.dev.release = platform_device_release;
 213		arch_setup_pdev_archdata(&pa->pdev);
 214	}
 215
 216	return pa ? &pa->pdev : NULL;
 217}
 218EXPORT_SYMBOL_GPL(platform_device_alloc);
 219
 220/**
 221 * platform_device_add_resources - add resources to a platform device
 222 * @pdev: platform device allocated by platform_device_alloc to add resources to
 223 * @res: set of resources that needs to be allocated for the device
 224 * @num: number of resources
 225 *
 226 * Add a copy of the resources to the platform device.  The memory
 227 * associated with the resources will be freed when the platform device is
 228 * released.
 229 */
 230int platform_device_add_resources(struct platform_device *pdev,
 231				  const struct resource *res, unsigned int num)
 232{
 233	struct resource *r = NULL;
 234
 235	if (res) {
 236		r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
 237		if (!r)
 238			return -ENOMEM;
 239	}
 240
 241	kfree(pdev->resource);
 242	pdev->resource = r;
 243	pdev->num_resources = num;
 244	return 0;
 245}
 246EXPORT_SYMBOL_GPL(platform_device_add_resources);
 247
 248/**
 249 * platform_device_add_data - add platform-specific data to a platform device
 250 * @pdev: platform device allocated by platform_device_alloc to add resources to
 251 * @data: platform specific data for this platform device
 252 * @size: size of platform specific data
 253 *
 254 * Add a copy of platform specific data to the platform device's
 255 * platform_data pointer.  The memory associated with the platform data
 256 * will be freed when the platform device is released.
 257 */
 258int platform_device_add_data(struct platform_device *pdev, const void *data,
 259			     size_t size)
 260{
 261	void *d = NULL;
 262
 263	if (data) {
 264		d = kmemdup(data, size, GFP_KERNEL);
 265		if (!d)
 266			return -ENOMEM;
 267	}
 268
 269	kfree(pdev->dev.platform_data);
 270	pdev->dev.platform_data = d;
 271	return 0;
 272}
 273EXPORT_SYMBOL_GPL(platform_device_add_data);
 274
 275/**
 276 * platform_device_add - add a platform device to device hierarchy
 277 * @pdev: platform device we're adding
 278 *
 279 * This is part 2 of platform_device_register(), though may be called
 280 * separately _iff_ pdev was allocated by platform_device_alloc().
 281 */
 282int platform_device_add(struct platform_device *pdev)
 283{
 284	int i, ret;
 
 285
 286	if (!pdev)
 287		return -EINVAL;
 288
 289	if (!pdev->dev.parent)
 290		pdev->dev.parent = &platform_bus;
 291
 292	pdev->dev.bus = &platform_bus_type;
 293
 294	switch (pdev->id) {
 295	default:
 296		dev_set_name(&pdev->dev, "%s.%d", pdev->name,  pdev->id);
 297		break;
 298	case PLATFORM_DEVID_NONE:
 299		dev_set_name(&pdev->dev, "%s", pdev->name);
 300		break;
 301	case PLATFORM_DEVID_AUTO:
 302		/*
 303		 * Automatically allocated device ID. We mark it as such so
 304		 * that we remember it must be freed, and we append a suffix
 305		 * to avoid namespace collision with explicit IDs.
 306		 */
 307		ret = ida_simple_get(&platform_devid_ida, 0, 0, GFP_KERNEL);
 308		if (ret < 0)
 309			goto err_out;
 310		pdev->id = ret;
 311		pdev->id_auto = true;
 312		dev_set_name(&pdev->dev, "%s.%d.auto", pdev->name, pdev->id);
 313		break;
 314	}
 315
 316	for (i = 0; i < pdev->num_resources; i++) {
 317		struct resource *p, *r = &pdev->resource[i];
 318
 319		if (r->name == NULL)
 320			r->name = dev_name(&pdev->dev);
 321
 322		p = r->parent;
 323		if (!p) {
 324			if (resource_type(r) == IORESOURCE_MEM)
 325				p = &iomem_resource;
 326			else if (resource_type(r) == IORESOURCE_IO)
 327				p = &ioport_resource;
 328		}
 329
 330		if (p && insert_resource(p, r)) {
 331			dev_err(&pdev->dev, "failed to claim resource %d\n", i);
 332			ret = -EBUSY;
 333			goto failed;
 
 
 334		}
 335	}
 336
 337	pr_debug("Registering platform device '%s'. Parent at %s\n",
 338		 dev_name(&pdev->dev), dev_name(pdev->dev.parent));
 339
 340	ret = device_add(&pdev->dev);
 341	if (ret == 0)
 342		return ret;
 343
 344 failed:
 345	if (pdev->id_auto) {
 346		ida_simple_remove(&platform_devid_ida, pdev->id);
 347		pdev->id = PLATFORM_DEVID_AUTO;
 348	}
 349
 350	while (--i >= 0) {
 351		struct resource *r = &pdev->resource[i];
 352		unsigned long type = resource_type(r);
 353
 354		if (type == IORESOURCE_MEM || type == IORESOURCE_IO)
 355			release_resource(r);
 356	}
 357
 358 err_out:
 359	return ret;
 360}
 361EXPORT_SYMBOL_GPL(platform_device_add);
 362
 363/**
 364 * platform_device_del - remove a platform-level device
 365 * @pdev: platform device we're removing
 366 *
 367 * Note that this function will also release all memory- and port-based
 368 * resources owned by the device (@dev->resource).  This function must
 369 * _only_ be externally called in error cases.  All other usage is a bug.
 370 */
 371void platform_device_del(struct platform_device *pdev)
 372{
 373	int i;
 374
 375	if (pdev) {
 376		device_del(&pdev->dev);
 377
 378		if (pdev->id_auto) {
 379			ida_simple_remove(&platform_devid_ida, pdev->id);
 380			pdev->id = PLATFORM_DEVID_AUTO;
 381		}
 382
 383		for (i = 0; i < pdev->num_resources; i++) {
 384			struct resource *r = &pdev->resource[i];
 385			unsigned long type = resource_type(r);
 386
 387			if (type == IORESOURCE_MEM || type == IORESOURCE_IO)
 388				release_resource(r);
 389		}
 390	}
 391}
 392EXPORT_SYMBOL_GPL(platform_device_del);
 393
 394/**
 395 * platform_device_register - add a platform-level device
 396 * @pdev: platform device we're adding
 
 
 
 
 397 */
 398int platform_device_register(struct platform_device *pdev)
 399{
 400	device_initialize(&pdev->dev);
 401	arch_setup_pdev_archdata(pdev);
 402	return platform_device_add(pdev);
 403}
 404EXPORT_SYMBOL_GPL(platform_device_register);
 405
 406/**
 407 * platform_device_unregister - unregister a platform-level device
 408 * @pdev: platform device we're unregistering
 409 *
 410 * Unregistration is done in 2 steps. First we release all resources
 411 * and remove it from the subsystem, then we drop reference count by
 412 * calling platform_device_put().
 413 */
 414void platform_device_unregister(struct platform_device *pdev)
 415{
 416	platform_device_del(pdev);
 417	platform_device_put(pdev);
 418}
 419EXPORT_SYMBOL_GPL(platform_device_unregister);
 420
 421/**
 422 * platform_device_register_full - add a platform-level device with
 423 * resources and platform-specific data
 424 *
 425 * @pdevinfo: data used to create device
 426 *
 427 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
 428 */
 429struct platform_device *platform_device_register_full(
 430		const struct platform_device_info *pdevinfo)
 431{
 432	int ret = -ENOMEM;
 433	struct platform_device *pdev;
 434
 435	pdev = platform_device_alloc(pdevinfo->name, pdevinfo->id);
 436	if (!pdev)
 437		goto err_alloc;
 438
 439	pdev->dev.parent = pdevinfo->parent;
 440	ACPI_COMPANION_SET(&pdev->dev, pdevinfo->acpi_node.companion);
 
 
 441
 442	if (pdevinfo->dma_mask) {
 443		/*
 444		 * This memory isn't freed when the device is put,
 445		 * I don't have a nice idea for that though.  Conceptually
 446		 * dma_mask in struct device should not be a pointer.
 447		 * See http://thread.gmane.org/gmane.linux.kernel.pci/9081
 448		 */
 449		pdev->dev.dma_mask =
 450			kmalloc(sizeof(*pdev->dev.dma_mask), GFP_KERNEL);
 451		if (!pdev->dev.dma_mask)
 452			goto err;
 453
 454		*pdev->dev.dma_mask = pdevinfo->dma_mask;
 455		pdev->dev.coherent_dma_mask = pdevinfo->dma_mask;
 456	}
 457
 458	ret = platform_device_add_resources(pdev,
 459			pdevinfo->res, pdevinfo->num_res);
 460	if (ret)
 461		goto err;
 462
 463	ret = platform_device_add_data(pdev,
 464			pdevinfo->data, pdevinfo->size_data);
 465	if (ret)
 466		goto err;
 467
 
 
 
 
 
 
 
 468	ret = platform_device_add(pdev);
 469	if (ret) {
 470err:
 471		ACPI_COMPANION_SET(&pdev->dev, NULL);
 472		kfree(pdev->dev.dma_mask);
 473
 474err_alloc:
 475		platform_device_put(pdev);
 476		return ERR_PTR(ret);
 477	}
 478
 479	return pdev;
 480}
 481EXPORT_SYMBOL_GPL(platform_device_register_full);
 482
 483static int platform_drv_probe(struct device *_dev)
 484{
 485	struct platform_driver *drv = to_platform_driver(_dev->driver);
 486	struct platform_device *dev = to_platform_device(_dev);
 487	int ret;
 488
 489	acpi_dev_pm_attach(_dev, true);
 490
 491	ret = drv->probe(dev);
 492	if (ret)
 493		acpi_dev_pm_detach(_dev, true);
 494
 495	if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
 496		dev_warn(_dev, "probe deferral not supported\n");
 497		ret = -ENXIO;
 498	}
 499
 500	return ret;
 501}
 502
 503static int platform_drv_probe_fail(struct device *_dev)
 504{
 505	return -ENXIO;
 506}
 507
 508static int platform_drv_remove(struct device *_dev)
 509{
 510	struct platform_driver *drv = to_platform_driver(_dev->driver);
 511	struct platform_device *dev = to_platform_device(_dev);
 512	int ret;
 513
 514	ret = drv->remove(dev);
 515	acpi_dev_pm_detach(_dev, true);
 516
 517	return ret;
 518}
 519
 520static void platform_drv_shutdown(struct device *_dev)
 521{
 522	struct platform_driver *drv = to_platform_driver(_dev->driver);
 523	struct platform_device *dev = to_platform_device(_dev);
 524
 525	drv->shutdown(dev);
 526	acpi_dev_pm_detach(_dev, true);
 527}
 528
 529/**
 530 * __platform_driver_register - register a driver for platform-level devices
 531 * @drv: platform driver structure
 532 * @owner: owning module/driver
 533 */
 534int __platform_driver_register(struct platform_driver *drv,
 535				struct module *owner)
 536{
 537	drv->driver.owner = owner;
 538	drv->driver.bus = &platform_bus_type;
 539	if (drv->probe)
 540		drv->driver.probe = platform_drv_probe;
 541	if (drv->remove)
 542		drv->driver.remove = platform_drv_remove;
 543	if (drv->shutdown)
 544		drv->driver.shutdown = platform_drv_shutdown;
 545
 546	return driver_register(&drv->driver);
 547}
 548EXPORT_SYMBOL_GPL(__platform_driver_register);
 549
 550/**
 551 * platform_driver_unregister - unregister a driver for platform-level devices
 552 * @drv: platform driver structure
 553 */
 554void platform_driver_unregister(struct platform_driver *drv)
 555{
 556	driver_unregister(&drv->driver);
 557}
 558EXPORT_SYMBOL_GPL(platform_driver_unregister);
 559
 
 
 
 
 
 560/**
 561 * platform_driver_probe - register driver for non-hotpluggable device
 562 * @drv: platform driver structure
 563 * @probe: the driver probe routine, probably from an __init section
 
 564 *
 565 * Use this instead of platform_driver_register() when you know the device
 566 * is not hotpluggable and has already been registered, and you want to
 567 * remove its run-once probe() infrastructure from memory after the driver
 568 * has bound to the device.
 569 *
 570 * One typical use for this would be with drivers for controllers integrated
 571 * into system-on-chip processors, where the controller devices have been
 572 * configured as part of board setup.
 573 *
 574 * Note that this is incompatible with deferred probing.
 575 *
 576 * Returns zero if the driver registered and bound to a device, else returns
 577 * a negative error code and with the driver not registered.
 578 */
 579int __init_or_module platform_driver_probe(struct platform_driver *drv,
 580		int (*probe)(struct platform_device *))
 581{
 582	int retval, code;
 583
 
 
 
 
 
 
 
 
 
 
 
 
 
 584	/*
 585	 * Prevent driver from requesting probe deferral to avoid further
 586	 * futile probe attempts.
 587	 */
 588	drv->prevent_deferred_probe = true;
 589
 590	/* make sure driver won't have bind/unbind attributes */
 591	drv->driver.suppress_bind_attrs = true;
 592
 593	/* temporary section violation during probe() */
 594	drv->probe = probe;
 595	retval = code = platform_driver_register(drv);
 
 
 596
 597	/*
 598	 * Fixup that section violation, being paranoid about code scanning
 599	 * the list of drivers in order to probe new devices.  Check to see
 600	 * if the probe was successful, and make sure any forced probes of
 601	 * new devices fail.
 602	 */
 603	spin_lock(&drv->driver.bus->p->klist_drivers.k_lock);
 604	drv->probe = NULL;
 605	if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
 606		retval = -ENODEV;
 607	drv->driver.probe = platform_drv_probe_fail;
 608	spin_unlock(&drv->driver.bus->p->klist_drivers.k_lock);
 609
 610	if (code != retval)
 611		platform_driver_unregister(drv);
 612	return retval;
 613}
 614EXPORT_SYMBOL_GPL(platform_driver_probe);
 615
 616/**
 617 * platform_create_bundle - register driver and create corresponding device
 618 * @driver: platform driver structure
 619 * @probe: the driver probe routine, probably from an __init section
 620 * @res: set of resources that needs to be allocated for the device
 621 * @n_res: number of resources
 622 * @data: platform specific data for this platform device
 623 * @size: size of platform specific data
 
 624 *
 625 * Use this in legacy-style modules that probe hardware directly and
 626 * register a single platform device and corresponding platform driver.
 627 *
 628 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
 629 */
 630struct platform_device * __init_or_module platform_create_bundle(
 631			struct platform_driver *driver,
 632			int (*probe)(struct platform_device *),
 633			struct resource *res, unsigned int n_res,
 634			const void *data, size_t size)
 635{
 636	struct platform_device *pdev;
 637	int error;
 638
 639	pdev = platform_device_alloc(driver->driver.name, -1);
 640	if (!pdev) {
 641		error = -ENOMEM;
 642		goto err_out;
 643	}
 644
 645	error = platform_device_add_resources(pdev, res, n_res);
 646	if (error)
 647		goto err_pdev_put;
 648
 649	error = platform_device_add_data(pdev, data, size);
 650	if (error)
 651		goto err_pdev_put;
 652
 653	error = platform_device_add(pdev);
 654	if (error)
 655		goto err_pdev_put;
 656
 657	error = platform_driver_probe(driver, probe);
 658	if (error)
 659		goto err_pdev_del;
 660
 661	return pdev;
 662
 663err_pdev_del:
 664	platform_device_del(pdev);
 665err_pdev_put:
 666	platform_device_put(pdev);
 667err_out:
 668	return ERR_PTR(error);
 669}
 670EXPORT_SYMBOL_GPL(platform_create_bundle);
 671
 672/* modalias support enables more hands-off userspace setup:
 673 * (a) environment variable lets new-style hotplug events work once system is
 674 *     fully running:  "modprobe $MODALIAS"
 675 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
 676 *     mishandled before system is fully running:  "modprobe $(cat modalias)"
 
 
 
 
 
 
 
 677 */
 678static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
 679			     char *buf)
 680{
 681	struct platform_device	*pdev = to_platform_device(dev);
 682	int len;
 683
 684	len = of_device_get_modalias(dev, buf, PAGE_SIZE -1);
 685	if (len != -ENODEV)
 686		return len;
 687
 688	len = acpi_device_modalias(dev, buf, PAGE_SIZE -1);
 689	if (len != -ENODEV)
 690		return len;
 
 
 
 
 691
 692	len = snprintf(buf, PAGE_SIZE, "platform:%s\n", pdev->name);
 693
 694	return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
 695}
 696static DEVICE_ATTR_RO(modalias);
 
 
 697
 698static struct attribute *platform_dev_attrs[] = {
 699	&dev_attr_modalias.attr,
 700	NULL,
 701};
 702ATTRIBUTE_GROUPS(platform_dev);
 703
 704static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
 
 
 
 
 
 
 
 
 
 
 705{
 706	struct platform_device	*pdev = to_platform_device(dev);
 707	int rc;
 708
 709	/* Some devices have extra OF data and an OF-style MODALIAS */
 710	rc = of_device_uevent_modalias(dev, env);
 711	if (rc != -ENODEV)
 712		return rc;
 713
 714	rc = acpi_device_uevent_modalias(dev, env);
 715	if (rc != -ENODEV)
 716		return rc;
 717
 718	add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
 719			pdev->name);
 720	return 0;
 721}
 
 722
 723static const struct platform_device_id *platform_match_id(
 724			const struct platform_device_id *id,
 725			struct platform_device *pdev)
 726{
 727	while (id->name[0]) {
 728		if (strcmp(pdev->name, id->name) == 0) {
 729			pdev->id_entry = id;
 730			return id;
 731		}
 732		id++;
 733	}
 734	return NULL;
 735}
 736
 737/**
 738 * platform_match - bind platform device to platform driver.
 739 * @dev: device.
 740 * @drv: driver.
 741 *
 742 * Platform device IDs are assumed to be encoded like this:
 743 * "<name><instance>", where <name> is a short description of the type of
 744 * device, like "pci" or "floppy", and <instance> is the enumerated
 745 * instance of the device, like '0' or '42'.  Driver IDs are simply
 746 * "<name>".  So, extract the <name> from the platform_device structure,
 747 * and compare it against the name of the driver. Return whether they match
 748 * or not.
 749 */
 750static int platform_match(struct device *dev, struct device_driver *drv)
 751{
 752	struct platform_device *pdev = to_platform_device(dev);
 753	struct platform_driver *pdrv = to_platform_driver(drv);
 754
 755	/* Attempt an OF style match first */
 756	if (of_driver_match_device(dev, drv))
 757		return 1;
 758
 759	/* Then try ACPI style match */
 760	if (acpi_driver_match_device(dev, drv))
 761		return 1;
 762
 763	/* Then try to match against the id table */
 764	if (pdrv->id_table)
 765		return platform_match_id(pdrv->id_table, pdev) != NULL;
 766
 767	/* fall-back to driver name match */
 768	return (strcmp(pdev->name, drv->name) == 0);
 769}
 770
 771#ifdef CONFIG_PM_SLEEP
 772
 773static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
 774{
 775	struct platform_driver *pdrv = to_platform_driver(dev->driver);
 776	struct platform_device *pdev = to_platform_device(dev);
 777	int ret = 0;
 778
 779	if (dev->driver && pdrv->suspend)
 780		ret = pdrv->suspend(pdev, mesg);
 781
 782	return ret;
 783}
 784
 785static int platform_legacy_resume(struct device *dev)
 786{
 787	struct platform_driver *pdrv = to_platform_driver(dev->driver);
 788	struct platform_device *pdev = to_platform_device(dev);
 789	int ret = 0;
 790
 791	if (dev->driver && pdrv->resume)
 792		ret = pdrv->resume(pdev);
 793
 794	return ret;
 795}
 796
 797#endif /* CONFIG_PM_SLEEP */
 798
 799#ifdef CONFIG_SUSPEND
 800
 801int platform_pm_suspend(struct device *dev)
 802{
 803	struct device_driver *drv = dev->driver;
 804	int ret = 0;
 805
 806	if (!drv)
 807		return 0;
 808
 809	if (drv->pm) {
 810		if (drv->pm->suspend)
 811			ret = drv->pm->suspend(dev);
 812	} else {
 813		ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
 814	}
 815
 816	return ret;
 817}
 818
 819int platform_pm_resume(struct device *dev)
 820{
 821	struct device_driver *drv = dev->driver;
 822	int ret = 0;
 823
 824	if (!drv)
 825		return 0;
 826
 827	if (drv->pm) {
 828		if (drv->pm->resume)
 829			ret = drv->pm->resume(dev);
 830	} else {
 831		ret = platform_legacy_resume(dev);
 832	}
 833
 834	return ret;
 835}
 836
 837#endif /* CONFIG_SUSPEND */
 838
 839#ifdef CONFIG_HIBERNATE_CALLBACKS
 840
 841int platform_pm_freeze(struct device *dev)
 842{
 843	struct device_driver *drv = dev->driver;
 844	int ret = 0;
 845
 846	if (!drv)
 847		return 0;
 848
 849	if (drv->pm) {
 850		if (drv->pm->freeze)
 851			ret = drv->pm->freeze(dev);
 852	} else {
 853		ret = platform_legacy_suspend(dev, PMSG_FREEZE);
 854	}
 855
 856	return ret;
 857}
 858
 859int platform_pm_thaw(struct device *dev)
 860{
 861	struct device_driver *drv = dev->driver;
 862	int ret = 0;
 863
 864	if (!drv)
 865		return 0;
 866
 867	if (drv->pm) {
 868		if (drv->pm->thaw)
 869			ret = drv->pm->thaw(dev);
 870	} else {
 871		ret = platform_legacy_resume(dev);
 872	}
 873
 874	return ret;
 875}
 876
 877int platform_pm_poweroff(struct device *dev)
 878{
 879	struct device_driver *drv = dev->driver;
 880	int ret = 0;
 881
 882	if (!drv)
 883		return 0;
 884
 885	if (drv->pm) {
 886		if (drv->pm->poweroff)
 887			ret = drv->pm->poweroff(dev);
 888	} else {
 889		ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
 890	}
 891
 892	return ret;
 893}
 894
 895int platform_pm_restore(struct device *dev)
 896{
 897	struct device_driver *drv = dev->driver;
 898	int ret = 0;
 899
 900	if (!drv)
 901		return 0;
 902
 903	if (drv->pm) {
 904		if (drv->pm->restore)
 905			ret = drv->pm->restore(dev);
 906	} else {
 907		ret = platform_legacy_resume(dev);
 908	}
 909
 910	return ret;
 911}
 912
 913#endif /* CONFIG_HIBERNATE_CALLBACKS */
 914
 915static const struct dev_pm_ops platform_dev_pm_ops = {
 916	.runtime_suspend = pm_generic_runtime_suspend,
 917	.runtime_resume = pm_generic_runtime_resume,
 918	USE_PLATFORM_PM_SLEEP_OPS
 919};
 
 
 
 
 
 
 920
 921struct bus_type platform_bus_type = {
 922	.name		= "platform",
 923	.dev_groups	= platform_dev_groups,
 924	.match		= platform_match,
 925	.uevent		= platform_uevent,
 926	.pm		= &platform_dev_pm_ops,
 927};
 928EXPORT_SYMBOL_GPL(platform_bus_type);
 929
 930int __init platform_bus_init(void)
 
 
 
 
 
 
 
 
 
 931{
 932	int error;
 
 
 933
 934	early_platform_cleanup();
 
 
 
 
 935
 936	error = device_register(&platform_bus);
 937	if (error)
 938		return error;
 939	error =  bus_register(&platform_bus_type);
 940	if (error)
 941		device_unregister(&platform_bus);
 942	return error;
 943}
 944
 945#ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
 946u64 dma_get_required_mask(struct device *dev)
 
 947{
 948	u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
 949	u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
 950	u64 mask;
 951
 952	if (!high_totalram) {
 953		/* convert to mask just covering totalram */
 954		low_totalram = (1 << (fls(low_totalram) - 1));
 955		low_totalram += low_totalram - 1;
 956		mask = low_totalram;
 957	} else {
 958		high_totalram = (1 << (fls(high_totalram) - 1));
 959		high_totalram += high_totalram - 1;
 960		mask = (((u64)high_totalram) << 32) + 0xffffffff;
 961	}
 962	return mask;
 963}
 964EXPORT_SYMBOL_GPL(dma_get_required_mask);
 965#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 966
 967static __initdata LIST_HEAD(early_platform_driver_list);
 968static __initdata LIST_HEAD(early_platform_device_list);
 969
 970/**
 971 * early_platform_driver_register - register early platform driver
 972 * @epdrv: early_platform driver structure
 973 * @buf: string passed from early_param()
 974 *
 975 * Helper function for early_platform_init() / early_platform_init_buffer()
 
 
 
 
 
 
 976 */
 977int __init early_platform_driver_register(struct early_platform_driver *epdrv,
 978					  char *buf)
 979{
 980	char *tmp;
 981	int n;
 982
 983	/* Simply add the driver to the end of the global list.
 984	 * Drivers will by default be put on the list in compiled-in order.
 985	 */
 986	if (!epdrv->list.next) {
 987		INIT_LIST_HEAD(&epdrv->list);
 988		list_add_tail(&epdrv->list, &early_platform_driver_list);
 989	}
 990
 991	/* If the user has specified device then make sure the driver
 992	 * gets prioritized. The driver of the last device specified on
 993	 * command line will be put first on the list.
 994	 */
 995	n = strlen(epdrv->pdrv->driver.name);
 996	if (buf && !strncmp(buf, epdrv->pdrv->driver.name, n)) {
 997		list_move(&epdrv->list, &early_platform_driver_list);
 998
 999		/* Allow passing parameters after device name */
1000		if (buf[n] == '\0' || buf[n] == ',')
1001			epdrv->requested_id = -1;
1002		else {
1003			epdrv->requested_id = simple_strtoul(&buf[n + 1],
1004							     &tmp, 10);
1005
1006			if (buf[n] != '.' || (tmp == &buf[n + 1])) {
1007				epdrv->requested_id = EARLY_PLATFORM_ID_ERROR;
1008				n = 0;
1009			} else
1010				n += strcspn(&buf[n + 1], ",") + 1;
1011		}
1012
1013		if (buf[n] == ',')
1014			n++;
 
1015
1016		if (epdrv->bufsize) {
1017			memcpy(epdrv->buffer, &buf[n],
1018			       min_t(int, epdrv->bufsize, strlen(&buf[n]) + 1));
1019			epdrv->buffer[epdrv->bufsize - 1] = '\0';
1020		}
1021	}
1022
1023	return 0;
 
1024}
1025
1026/**
1027 * early_platform_add_devices - adds a number of early platform devices
1028 * @devs: array of early platform devices to add
1029 * @num: number of early platform devices in array
1030 *
1031 * Used by early architecture code to register early platform devices and
1032 * their platform data.
1033 */
1034void __init early_platform_add_devices(struct platform_device **devs, int num)
1035{
1036	struct device *dev;
1037	int i;
1038
1039	/* simply add the devices to list */
1040	for (i = 0; i < num; i++) {
1041		dev = &devs[i]->dev;
 
1042
1043		if (!dev->devres_head.next) {
1044			pm_runtime_early_init(dev);
1045			INIT_LIST_HEAD(&dev->devres_head);
1046			list_add_tail(&dev->devres_head,
1047				      &early_platform_device_list);
1048		}
1049	}
1050}
1051
1052/**
1053 * early_platform_driver_register_all - register early platform drivers
1054 * @class_str: string to identify early platform driver class
1055 *
1056 * Used by architecture code to register all early platform drivers
1057 * for a certain class. If omitted then only early platform drivers
1058 * with matching kernel command line class parameters will be registered.
1059 */
1060void __init early_platform_driver_register_all(char *class_str)
1061{
1062	/* The "class_str" parameter may or may not be present on the kernel
1063	 * command line. If it is present then there may be more than one
1064	 * matching parameter.
1065	 *
1066	 * Since we register our early platform drivers using early_param()
1067	 * we need to make sure that they also get registered in the case
1068	 * when the parameter is missing from the kernel command line.
1069	 *
1070	 * We use parse_early_options() to make sure the early_param() gets
1071	 * called at least once. The early_param() may be called more than
1072	 * once since the name of the preferred device may be specified on
1073	 * the kernel command line. early_platform_driver_register() handles
1074	 * this case for us.
1075	 */
1076	parse_early_options(class_str);
1077}
1078
1079/**
1080 * early_platform_match - find early platform device matching driver
1081 * @epdrv: early platform driver structure
1082 * @id: id to match against
1083 */
1084static struct platform_device * __init
1085early_platform_match(struct early_platform_driver *epdrv, int id)
1086{
1087	struct platform_device *pd;
 
 
1088
1089	list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1090		if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1091			if (pd->id == id)
1092				return pd;
 
 
 
 
 
1093
1094	return NULL;
1095}
 
1096
1097/**
1098 * early_platform_left - check if early platform driver has matching devices
1099 * @epdrv: early platform driver structure
1100 * @id: return true if id or above exists
1101 */
1102static int __init early_platform_left(struct early_platform_driver *epdrv,
1103				       int id)
1104{
1105	struct platform_device *pd;
1106
1107	list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1108		if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1109			if (pd->id >= id)
1110				return 1;
1111
1112	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
1113}
1114
1115/**
1116 * early_platform_driver_probe_id - probe drivers matching class_str and id
1117 * @class_str: string to identify early platform driver class
1118 * @id: id to match against
1119 * @nr_probe: number of platform devices to successfully probe before exiting
1120 */
1121static int __init early_platform_driver_probe_id(char *class_str,
1122						 int id,
1123						 int nr_probe)
1124{
1125	struct early_platform_driver *epdrv;
1126	struct platform_device *match;
1127	int match_id;
1128	int n = 0;
1129	int left = 0;
1130
1131	list_for_each_entry(epdrv, &early_platform_driver_list, list) {
1132		/* only use drivers matching our class_str */
1133		if (strcmp(class_str, epdrv->class_str))
1134			continue;
1135
1136		if (id == -2) {
1137			match_id = epdrv->requested_id;
1138			left = 1;
1139
1140		} else {
1141			match_id = id;
1142			left += early_platform_left(epdrv, id);
1143
1144			/* skip requested id */
1145			switch (epdrv->requested_id) {
1146			case EARLY_PLATFORM_ID_ERROR:
1147			case EARLY_PLATFORM_ID_UNSET:
1148				break;
1149			default:
1150				if (epdrv->requested_id == id)
1151					match_id = EARLY_PLATFORM_ID_UNSET;
1152			}
1153		}
1154
1155		switch (match_id) {
1156		case EARLY_PLATFORM_ID_ERROR:
1157			pr_warn("%s: unable to parse %s parameter\n",
1158				class_str, epdrv->pdrv->driver.name);
1159			/* fall-through */
1160		case EARLY_PLATFORM_ID_UNSET:
1161			match = NULL;
1162			break;
1163		default:
1164			match = early_platform_match(epdrv, match_id);
1165		}
1166
1167		if (match) {
1168			/*
1169			 * Set up a sensible init_name to enable
1170			 * dev_name() and others to be used before the
1171			 * rest of the driver core is initialized.
1172			 */
1173			if (!match->dev.init_name && slab_is_available()) {
1174				if (match->id != -1)
1175					match->dev.init_name =
1176						kasprintf(GFP_KERNEL, "%s.%d",
1177							  match->name,
1178							  match->id);
1179				else
1180					match->dev.init_name =
1181						kasprintf(GFP_KERNEL, "%s",
1182							  match->name);
1183
1184				if (!match->dev.init_name)
1185					return -ENOMEM;
1186			}
1187
1188			if (epdrv->pdrv->probe(match))
1189				pr_warn("%s: unable to probe %s early.\n",
1190					class_str, match->name);
1191			else
1192				n++;
1193		}
1194
1195		if (n >= nr_probe)
1196			break;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1197	}
1198
1199	if (left)
1200		return n;
1201	else
1202		return -ENODEV;
1203}
1204
1205/**
1206 * early_platform_driver_probe - probe a class of registered drivers
1207 * @class_str: string to identify early platform driver class
1208 * @nr_probe: number of platform devices to successfully probe before exiting
1209 * @user_only: only probe user specified early platform devices
1210 *
1211 * Used by architecture code to probe registered early platform drivers
1212 * within a certain class. For probe to happen a registered early platform
1213 * device matching a registered early platform driver is needed.
1214 */
1215int __init early_platform_driver_probe(char *class_str,
1216				       int nr_probe,
1217				       int user_only)
1218{
1219	int k, n, i;
1220
1221	n = 0;
1222	for (i = -2; n < nr_probe; i++) {
1223		k = early_platform_driver_probe_id(class_str, i, nr_probe - n);
1224
1225		if (k < 0)
1226			break;
1227
1228		n += k;
 
 
 
1229
1230		if (user_only)
1231			break;
1232	}
 
 
 
 
 
 
 
 
 
 
1233
1234	return n;
 
 
1235}
1236
1237/**
1238 * early_platform_cleanup - clean up early platform code
 
 
 
1239 */
1240void __init early_platform_cleanup(void)
 
 
 
 
 
 
 
 
 
 
1241{
1242	struct platform_device *pd, *pd2;
 
 
1243
1244	/* clean up the devres list used to chain devices */
1245	list_for_each_entry_safe(pd, pd2, &early_platform_device_list,
1246				 dev.devres_head) {
1247		list_del(&pd->dev.devres_head);
1248		memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head));
1249	}
 
 
 
 
 
1250}
1251
v6.2
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * platform.c - platform 'pseudo' bus for legacy devices
   4 *
   5 * Copyright (c) 2002-3 Patrick Mochel
   6 * Copyright (c) 2002-3 Open Source Development Labs
   7 *
   8 * Please see Documentation/driver-api/driver-model/platform.rst for more
 
 
   9 * information.
  10 */
  11
  12#include <linux/string.h>
  13#include <linux/platform_device.h>
  14#include <linux/of_device.h>
  15#include <linux/of_irq.h>
  16#include <linux/module.h>
  17#include <linux/init.h>
  18#include <linux/interrupt.h>
  19#include <linux/ioport.h>
  20#include <linux/dma-mapping.h>
  21#include <linux/memblock.h>
  22#include <linux/err.h>
  23#include <linux/slab.h>
  24#include <linux/pm_runtime.h>
  25#include <linux/pm_domain.h>
  26#include <linux/idr.h>
  27#include <linux/acpi.h>
  28#include <linux/clk/clk-conf.h>
  29#include <linux/limits.h>
  30#include <linux/property.h>
  31#include <linux/kmemleak.h>
  32#include <linux/types.h>
  33#include <linux/iommu.h>
  34#include <linux/dma-map-ops.h>
  35
  36#include "base.h"
  37#include "power/power.h"
  38
  39/* For automatically allocated device IDs */
  40static DEFINE_IDA(platform_devid_ida);
  41
  42struct device platform_bus = {
  43	.init_name	= "platform",
  44};
  45EXPORT_SYMBOL_GPL(platform_bus);
  46
  47/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  48 * platform_get_resource - get a resource for a device
  49 * @dev: platform device
  50 * @type: resource type
  51 * @num: resource index
  52 *
  53 * Return: a pointer to the resource or NULL on failure.
  54 */
  55struct resource *platform_get_resource(struct platform_device *dev,
  56				       unsigned int type, unsigned int num)
  57{
  58	u32 i;
  59
  60	for (i = 0; i < dev->num_resources; i++) {
  61		struct resource *r = &dev->resource[i];
  62
  63		if (type == resource_type(r) && num-- == 0)
  64			return r;
  65	}
  66	return NULL;
  67}
  68EXPORT_SYMBOL_GPL(platform_get_resource);
  69
  70struct resource *platform_get_mem_or_io(struct platform_device *dev,
  71					unsigned int num)
  72{
  73	u32 i;
  74
  75	for (i = 0; i < dev->num_resources; i++) {
  76		struct resource *r = &dev->resource[i];
  77
  78		if ((resource_type(r) & (IORESOURCE_MEM|IORESOURCE_IO)) && num-- == 0)
  79			return r;
  80	}
  81	return NULL;
  82}
  83EXPORT_SYMBOL_GPL(platform_get_mem_or_io);
  84
  85#ifdef CONFIG_HAS_IOMEM
  86/**
  87 * devm_platform_get_and_ioremap_resource - call devm_ioremap_resource() for a
  88 *					    platform device and get resource
  89 *
  90 * @pdev: platform device to use both for memory resource lookup as well as
  91 *        resource management
  92 * @index: resource index
  93 * @res: optional output parameter to store a pointer to the obtained resource.
  94 *
  95 * Return: a pointer to the remapped memory or an ERR_PTR() encoded error code
  96 * on failure.
  97 */
  98void __iomem *
  99devm_platform_get_and_ioremap_resource(struct platform_device *pdev,
 100				unsigned int index, struct resource **res)
 101{
 102	struct resource *r;
 103
 104	r = platform_get_resource(pdev, IORESOURCE_MEM, index);
 105	if (res)
 106		*res = r;
 107	return devm_ioremap_resource(&pdev->dev, r);
 108}
 109EXPORT_SYMBOL_GPL(devm_platform_get_and_ioremap_resource);
 110
 111/**
 112 * devm_platform_ioremap_resource - call devm_ioremap_resource() for a platform
 113 *				    device
 114 *
 115 * @pdev: platform device to use both for memory resource lookup as well as
 116 *        resource management
 117 * @index: resource index
 118 *
 119 * Return: a pointer to the remapped memory or an ERR_PTR() encoded error code
 120 * on failure.
 121 */
 122void __iomem *devm_platform_ioremap_resource(struct platform_device *pdev,
 123					     unsigned int index)
 124{
 125	return devm_platform_get_and_ioremap_resource(pdev, index, NULL);
 126}
 127EXPORT_SYMBOL_GPL(devm_platform_ioremap_resource);
 128
 129/**
 130 * devm_platform_ioremap_resource_byname - call devm_ioremap_resource for
 131 *					   a platform device, retrieve the
 132 *					   resource by name
 133 *
 134 * @pdev: platform device to use both for memory resource lookup as well as
 135 *	  resource management
 136 * @name: name of the resource
 137 *
 138 * Return: a pointer to the remapped memory or an ERR_PTR() encoded error code
 139 * on failure.
 140 */
 141void __iomem *
 142devm_platform_ioremap_resource_byname(struct platform_device *pdev,
 143				      const char *name)
 144{
 145	struct resource *res;
 146
 147	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, name);
 148	return devm_ioremap_resource(&pdev->dev, res);
 149}
 150EXPORT_SYMBOL_GPL(devm_platform_ioremap_resource_byname);
 151#endif /* CONFIG_HAS_IOMEM */
 152
 153/**
 154 * platform_get_irq_optional - get an optional IRQ for a device
 155 * @dev: platform device
 156 * @num: IRQ number index
 157 *
 158 * Gets an IRQ for a platform device. Device drivers should check the return
 159 * value for errors so as to not pass a negative integer value to the
 160 * request_irq() APIs. This is the same as platform_get_irq(), except that it
 161 * does not print an error message if an IRQ can not be obtained.
 162 *
 163 * For example::
 164 *
 165 *		int irq = platform_get_irq_optional(pdev, 0);
 166 *		if (irq < 0)
 167 *			return irq;
 168 *
 169 * Return: non-zero IRQ number on success, negative error number on failure.
 170 */
 171int platform_get_irq_optional(struct platform_device *dev, unsigned int num)
 172{
 173	int ret;
 174#ifdef CONFIG_SPARC
 175	/* sparc does not have irqs represented as IORESOURCE_IRQ resources */
 176	if (!dev || num >= dev->archdata.num_irqs)
 177		goto out_not_found;
 178	ret = dev->archdata.irqs[num];
 179	goto out;
 180#else
 181	struct resource *r;
 182
 183	if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
 184		ret = of_irq_get(dev->dev.of_node, num);
 185		if (ret > 0 || ret == -EPROBE_DEFER)
 186			goto out;
 187	}
 188
 189	r = platform_get_resource(dev, IORESOURCE_IRQ, num);
 190	if (has_acpi_companion(&dev->dev)) {
 191		if (r && r->flags & IORESOURCE_DISABLED) {
 192			ret = acpi_irq_get(ACPI_HANDLE(&dev->dev), num, r);
 193			if (ret)
 194				goto out;
 195		}
 196	}
 197
 198	/*
 199	 * The resources may pass trigger flags to the irqs that need
 200	 * to be set up. It so happens that the trigger flags for
 201	 * IORESOURCE_BITS correspond 1-to-1 to the IRQF_TRIGGER*
 202	 * settings.
 203	 */
 204	if (r && r->flags & IORESOURCE_BITS) {
 205		struct irq_data *irqd;
 206
 207		irqd = irq_get_irq_data(r->start);
 208		if (!irqd)
 209			goto out_not_found;
 210		irqd_set_trigger_type(irqd, r->flags & IORESOURCE_BITS);
 211	}
 212
 213	if (r) {
 214		ret = r->start;
 215		goto out;
 216	}
 217
 218	/*
 219	 * For the index 0 interrupt, allow falling back to GpioInt
 220	 * resources. While a device could have both Interrupt and GpioInt
 221	 * resources, making this fallback ambiguous, in many common cases
 222	 * the device will only expose one IRQ, and this fallback
 223	 * allows a common code path across either kind of resource.
 224	 */
 225	if (num == 0 && has_acpi_companion(&dev->dev)) {
 226		ret = acpi_dev_gpio_irq_get(ACPI_COMPANION(&dev->dev), num);
 227		/* Our callers expect -ENXIO for missing IRQs. */
 228		if (ret >= 0 || ret == -EPROBE_DEFER)
 229			goto out;
 230	}
 231
 
 232#endif
 233out_not_found:
 234	ret = -ENXIO;
 235out:
 236	if (WARN(!ret, "0 is an invalid IRQ number\n"))
 237		return -EINVAL;
 238	return ret;
 239}
 240EXPORT_SYMBOL_GPL(platform_get_irq_optional);
 241
 242/**
 243 * platform_get_irq - get an IRQ for a device
 244 * @dev: platform device
 245 * @num: IRQ number index
 246 *
 247 * Gets an IRQ for a platform device and prints an error message if finding the
 248 * IRQ fails. Device drivers should check the return value for errors so as to
 249 * not pass a negative integer value to the request_irq() APIs.
 250 *
 251 * For example::
 252 *
 253 *		int irq = platform_get_irq(pdev, 0);
 254 *		if (irq < 0)
 255 *			return irq;
 256 *
 257 * Return: non-zero IRQ number on success, negative error number on failure.
 258 */
 259int platform_get_irq(struct platform_device *dev, unsigned int num)
 260{
 261	int ret;
 262
 263	ret = platform_get_irq_optional(dev, num);
 264	if (ret < 0)
 265		return dev_err_probe(&dev->dev, ret,
 266				     "IRQ index %u not found\n", num);
 267
 268	return ret;
 269}
 270EXPORT_SYMBOL_GPL(platform_get_irq);
 271
 272/**
 273 * platform_irq_count - Count the number of IRQs a platform device uses
 274 * @dev: platform device
 275 *
 276 * Return: Number of IRQs a platform device uses or EPROBE_DEFER
 277 */
 278int platform_irq_count(struct platform_device *dev)
 279{
 280	int ret, nr = 0;
 281
 282	while ((ret = platform_get_irq_optional(dev, nr)) >= 0)
 283		nr++;
 284
 285	if (ret == -EPROBE_DEFER)
 286		return ret;
 287
 288	return nr;
 289}
 290EXPORT_SYMBOL_GPL(platform_irq_count);
 291
 292struct irq_affinity_devres {
 293	unsigned int count;
 294	unsigned int irq[];
 295};
 296
 297static void platform_disable_acpi_irq(struct platform_device *pdev, int index)
 298{
 299	struct resource *r;
 300
 301	r = platform_get_resource(pdev, IORESOURCE_IRQ, index);
 302	if (r)
 303		irqresource_disabled(r, 0);
 304}
 305
 306static void devm_platform_get_irqs_affinity_release(struct device *dev,
 307						    void *res)
 308{
 309	struct irq_affinity_devres *ptr = res;
 310	int i;
 311
 312	for (i = 0; i < ptr->count; i++) {
 313		irq_dispose_mapping(ptr->irq[i]);
 314
 315		if (has_acpi_companion(dev))
 316			platform_disable_acpi_irq(to_platform_device(dev), i);
 317	}
 318}
 319
 320/**
 321 * devm_platform_get_irqs_affinity - devm method to get a set of IRQs for a
 322 *				device using an interrupt affinity descriptor
 323 * @dev: platform device pointer
 324 * @affd: affinity descriptor
 325 * @minvec: minimum count of interrupt vectors
 326 * @maxvec: maximum count of interrupt vectors
 327 * @irqs: pointer holder for IRQ numbers
 328 *
 329 * Gets a set of IRQs for a platform device, and updates IRQ afffinty according
 330 * to the passed affinity descriptor
 331 *
 332 * Return: Number of vectors on success, negative error number on failure.
 333 */
 334int devm_platform_get_irqs_affinity(struct platform_device *dev,
 335				    struct irq_affinity *affd,
 336				    unsigned int minvec,
 337				    unsigned int maxvec,
 338				    int **irqs)
 339{
 340	struct irq_affinity_devres *ptr;
 341	struct irq_affinity_desc *desc;
 342	size_t size;
 343	int i, ret, nvec;
 344
 345	if (!affd)
 346		return -EPERM;
 347
 348	if (maxvec < minvec)
 349		return -ERANGE;
 350
 351	nvec = platform_irq_count(dev);
 352	if (nvec < 0)
 353		return nvec;
 354
 355	if (nvec < minvec)
 356		return -ENOSPC;
 357
 358	nvec = irq_calc_affinity_vectors(minvec, nvec, affd);
 359	if (nvec < minvec)
 360		return -ENOSPC;
 361
 362	if (nvec > maxvec)
 363		nvec = maxvec;
 364
 365	size = sizeof(*ptr) + sizeof(unsigned int) * nvec;
 366	ptr = devres_alloc(devm_platform_get_irqs_affinity_release, size,
 367			   GFP_KERNEL);
 368	if (!ptr)
 369		return -ENOMEM;
 370
 371	ptr->count = nvec;
 372
 373	for (i = 0; i < nvec; i++) {
 374		int irq = platform_get_irq(dev, i);
 375		if (irq < 0) {
 376			ret = irq;
 377			goto err_free_devres;
 378		}
 379		ptr->irq[i] = irq;
 380	}
 381
 382	desc = irq_create_affinity_masks(nvec, affd);
 383	if (!desc) {
 384		ret = -ENOMEM;
 385		goto err_free_devres;
 386	}
 387
 388	for (i = 0; i < nvec; i++) {
 389		ret = irq_update_affinity_desc(ptr->irq[i], &desc[i]);
 390		if (ret) {
 391			dev_err(&dev->dev, "failed to update irq%d affinity descriptor (%d)\n",
 392				ptr->irq[i], ret);
 393			goto err_free_desc;
 394		}
 395	}
 396
 397	devres_add(&dev->dev, ptr);
 398
 399	kfree(desc);
 400
 401	*irqs = ptr->irq;
 402
 403	return nvec;
 404
 405err_free_desc:
 406	kfree(desc);
 407err_free_devres:
 408	devres_free(ptr);
 409	return ret;
 410}
 411EXPORT_SYMBOL_GPL(devm_platform_get_irqs_affinity);
 412
 413/**
 414 * platform_get_resource_byname - get a resource for a device by name
 415 * @dev: platform device
 416 * @type: resource type
 417 * @name: resource name
 418 */
 419struct resource *platform_get_resource_byname(struct platform_device *dev,
 420					      unsigned int type,
 421					      const char *name)
 422{
 423	u32 i;
 424
 425	for (i = 0; i < dev->num_resources; i++) {
 426		struct resource *r = &dev->resource[i];
 427
 428		if (unlikely(!r->name))
 429			continue;
 430
 431		if (type == resource_type(r) && !strcmp(r->name, name))
 432			return r;
 433	}
 434	return NULL;
 435}
 436EXPORT_SYMBOL_GPL(platform_get_resource_byname);
 437
 438static int __platform_get_irq_byname(struct platform_device *dev,
 439				     const char *name)
 440{
 441	struct resource *r;
 442	int ret;
 443
 444	if (!dev->dev.of_node || IS_ENABLED(CONFIG_OF_IRQ)) {
 445		ret = fwnode_irq_get_byname(dev_fwnode(&dev->dev), name);
 446		if (ret > 0 || ret == -EPROBE_DEFER)
 447			return ret;
 448	}
 449
 450	r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name);
 451	if (r) {
 452		if (WARN(!r->start, "0 is an invalid IRQ number\n"))
 453			return -EINVAL;
 454		return r->start;
 455	}
 456
 457	return -ENXIO;
 458}
 459
 460/**
 461 * platform_get_irq_byname - get an IRQ for a device by name
 462 * @dev: platform device
 463 * @name: IRQ name
 464 *
 465 * Get an IRQ like platform_get_irq(), but then by name rather then by index.
 466 *
 467 * Return: non-zero IRQ number on success, negative error number on failure.
 468 */
 469int platform_get_irq_byname(struct platform_device *dev, const char *name)
 470{
 471	int ret;
 
 472
 473	ret = __platform_get_irq_byname(dev, name);
 474	if (ret < 0)
 475		return dev_err_probe(&dev->dev, ret, "IRQ %s not found\n",
 476				     name);
 477	return ret;
 478}
 479EXPORT_SYMBOL_GPL(platform_get_irq_byname);
 480
 481/**
 482 * platform_get_irq_byname_optional - get an optional IRQ for a device by name
 483 * @dev: platform device
 484 * @name: IRQ name
 485 *
 486 * Get an optional IRQ by name like platform_get_irq_byname(). Except that it
 487 * does not print an error message if an IRQ can not be obtained.
 488 *
 489 * Return: non-zero IRQ number on success, negative error number on failure.
 490 */
 491int platform_get_irq_byname_optional(struct platform_device *dev,
 492				     const char *name)
 493{
 494	return __platform_get_irq_byname(dev, name);
 495}
 496EXPORT_SYMBOL_GPL(platform_get_irq_byname_optional);
 497
 498/**
 499 * platform_add_devices - add a numbers of platform devices
 500 * @devs: array of platform devices to add
 501 * @num: number of platform devices in array
 502 */
 503int platform_add_devices(struct platform_device **devs, int num)
 504{
 505	int i, ret = 0;
 506
 507	for (i = 0; i < num; i++) {
 508		ret = platform_device_register(devs[i]);
 509		if (ret) {
 510			while (--i >= 0)
 511				platform_device_unregister(devs[i]);
 512			break;
 513		}
 514	}
 515
 516	return ret;
 517}
 518EXPORT_SYMBOL_GPL(platform_add_devices);
 519
 520struct platform_object {
 521	struct platform_device pdev;
 522	char name[];
 523};
 524
 525/*
 526 * Set up default DMA mask for platform devices if the they weren't
 527 * previously set by the architecture / DT.
 528 */
 529static void setup_pdev_dma_masks(struct platform_device *pdev)
 530{
 531	pdev->dev.dma_parms = &pdev->dma_parms;
 532
 533	if (!pdev->dev.coherent_dma_mask)
 534		pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
 535	if (!pdev->dev.dma_mask) {
 536		pdev->platform_dma_mask = DMA_BIT_MASK(32);
 537		pdev->dev.dma_mask = &pdev->platform_dma_mask;
 538	}
 539};
 540
 541/**
 542 * platform_device_put - destroy a platform device
 543 * @pdev: platform device to free
 544 *
 545 * Free all memory associated with a platform device.  This function must
 546 * _only_ be externally called in error cases.  All other usage is a bug.
 547 */
 548void platform_device_put(struct platform_device *pdev)
 549{
 550	if (!IS_ERR_OR_NULL(pdev))
 551		put_device(&pdev->dev);
 552}
 553EXPORT_SYMBOL_GPL(platform_device_put);
 554
 555static void platform_device_release(struct device *dev)
 556{
 557	struct platform_object *pa = container_of(dev, struct platform_object,
 558						  pdev.dev);
 559
 560	of_node_put(pa->pdev.dev.of_node);
 561	kfree(pa->pdev.dev.platform_data);
 562	kfree(pa->pdev.mfd_cell);
 563	kfree(pa->pdev.resource);
 564	kfree(pa->pdev.driver_override);
 565	kfree(pa);
 566}
 567
 568/**
 569 * platform_device_alloc - create a platform device
 570 * @name: base name of the device we're adding
 571 * @id: instance id
 572 *
 573 * Create a platform device object which can have other objects attached
 574 * to it, and which will have attached objects freed when it is released.
 575 */
 576struct platform_device *platform_device_alloc(const char *name, int id)
 577{
 578	struct platform_object *pa;
 579
 580	pa = kzalloc(sizeof(*pa) + strlen(name) + 1, GFP_KERNEL);
 581	if (pa) {
 582		strcpy(pa->name, name);
 583		pa->pdev.name = pa->name;
 584		pa->pdev.id = id;
 585		device_initialize(&pa->pdev.dev);
 586		pa->pdev.dev.release = platform_device_release;
 587		setup_pdev_dma_masks(&pa->pdev);
 588	}
 589
 590	return pa ? &pa->pdev : NULL;
 591}
 592EXPORT_SYMBOL_GPL(platform_device_alloc);
 593
 594/**
 595 * platform_device_add_resources - add resources to a platform device
 596 * @pdev: platform device allocated by platform_device_alloc to add resources to
 597 * @res: set of resources that needs to be allocated for the device
 598 * @num: number of resources
 599 *
 600 * Add a copy of the resources to the platform device.  The memory
 601 * associated with the resources will be freed when the platform device is
 602 * released.
 603 */
 604int platform_device_add_resources(struct platform_device *pdev,
 605				  const struct resource *res, unsigned int num)
 606{
 607	struct resource *r = NULL;
 608
 609	if (res) {
 610		r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
 611		if (!r)
 612			return -ENOMEM;
 613	}
 614
 615	kfree(pdev->resource);
 616	pdev->resource = r;
 617	pdev->num_resources = num;
 618	return 0;
 619}
 620EXPORT_SYMBOL_GPL(platform_device_add_resources);
 621
 622/**
 623 * platform_device_add_data - add platform-specific data to a platform device
 624 * @pdev: platform device allocated by platform_device_alloc to add resources to
 625 * @data: platform specific data for this platform device
 626 * @size: size of platform specific data
 627 *
 628 * Add a copy of platform specific data to the platform device's
 629 * platform_data pointer.  The memory associated with the platform data
 630 * will be freed when the platform device is released.
 631 */
 632int platform_device_add_data(struct platform_device *pdev, const void *data,
 633			     size_t size)
 634{
 635	void *d = NULL;
 636
 637	if (data) {
 638		d = kmemdup(data, size, GFP_KERNEL);
 639		if (!d)
 640			return -ENOMEM;
 641	}
 642
 643	kfree(pdev->dev.platform_data);
 644	pdev->dev.platform_data = d;
 645	return 0;
 646}
 647EXPORT_SYMBOL_GPL(platform_device_add_data);
 648
 649/**
 650 * platform_device_add - add a platform device to device hierarchy
 651 * @pdev: platform device we're adding
 652 *
 653 * This is part 2 of platform_device_register(), though may be called
 654 * separately _iff_ pdev was allocated by platform_device_alloc().
 655 */
 656int platform_device_add(struct platform_device *pdev)
 657{
 658	u32 i;
 659	int ret;
 660
 661	if (!pdev)
 662		return -EINVAL;
 663
 664	if (!pdev->dev.parent)
 665		pdev->dev.parent = &platform_bus;
 666
 667	pdev->dev.bus = &platform_bus_type;
 668
 669	switch (pdev->id) {
 670	default:
 671		dev_set_name(&pdev->dev, "%s.%d", pdev->name,  pdev->id);
 672		break;
 673	case PLATFORM_DEVID_NONE:
 674		dev_set_name(&pdev->dev, "%s", pdev->name);
 675		break;
 676	case PLATFORM_DEVID_AUTO:
 677		/*
 678		 * Automatically allocated device ID. We mark it as such so
 679		 * that we remember it must be freed, and we append a suffix
 680		 * to avoid namespace collision with explicit IDs.
 681		 */
 682		ret = ida_alloc(&platform_devid_ida, GFP_KERNEL);
 683		if (ret < 0)
 684			goto err_out;
 685		pdev->id = ret;
 686		pdev->id_auto = true;
 687		dev_set_name(&pdev->dev, "%s.%d.auto", pdev->name, pdev->id);
 688		break;
 689	}
 690
 691	for (i = 0; i < pdev->num_resources; i++) {
 692		struct resource *p, *r = &pdev->resource[i];
 693
 694		if (r->name == NULL)
 695			r->name = dev_name(&pdev->dev);
 696
 697		p = r->parent;
 698		if (!p) {
 699			if (resource_type(r) == IORESOURCE_MEM)
 700				p = &iomem_resource;
 701			else if (resource_type(r) == IORESOURCE_IO)
 702				p = &ioport_resource;
 703		}
 704
 705		if (p) {
 706			ret = insert_resource(p, r);
 707			if (ret) {
 708				dev_err(&pdev->dev, "failed to claim resource %d: %pR\n", i, r);
 709				goto failed;
 710			}
 711		}
 712	}
 713
 714	pr_debug("Registering platform device '%s'. Parent at %s\n",
 715		 dev_name(&pdev->dev), dev_name(pdev->dev.parent));
 716
 717	ret = device_add(&pdev->dev);
 718	if (ret == 0)
 719		return ret;
 720
 721 failed:
 722	if (pdev->id_auto) {
 723		ida_free(&platform_devid_ida, pdev->id);
 724		pdev->id = PLATFORM_DEVID_AUTO;
 725	}
 726
 727	while (i--) {
 728		struct resource *r = &pdev->resource[i];
 729		if (r->parent)
 
 
 730			release_resource(r);
 731	}
 732
 733 err_out:
 734	return ret;
 735}
 736EXPORT_SYMBOL_GPL(platform_device_add);
 737
 738/**
 739 * platform_device_del - remove a platform-level device
 740 * @pdev: platform device we're removing
 741 *
 742 * Note that this function will also release all memory- and port-based
 743 * resources owned by the device (@dev->resource).  This function must
 744 * _only_ be externally called in error cases.  All other usage is a bug.
 745 */
 746void platform_device_del(struct platform_device *pdev)
 747{
 748	u32 i;
 749
 750	if (!IS_ERR_OR_NULL(pdev)) {
 751		device_del(&pdev->dev);
 752
 753		if (pdev->id_auto) {
 754			ida_free(&platform_devid_ida, pdev->id);
 755			pdev->id = PLATFORM_DEVID_AUTO;
 756		}
 757
 758		for (i = 0; i < pdev->num_resources; i++) {
 759			struct resource *r = &pdev->resource[i];
 760			if (r->parent)
 
 
 761				release_resource(r);
 762		}
 763	}
 764}
 765EXPORT_SYMBOL_GPL(platform_device_del);
 766
 767/**
 768 * platform_device_register - add a platform-level device
 769 * @pdev: platform device we're adding
 770 *
 771 * NOTE: _Never_ directly free @pdev after calling this function, even if it
 772 * returned an error! Always use platform_device_put() to give up the
 773 * reference initialised in this function instead.
 774 */
 775int platform_device_register(struct platform_device *pdev)
 776{
 777	device_initialize(&pdev->dev);
 778	setup_pdev_dma_masks(pdev);
 779	return platform_device_add(pdev);
 780}
 781EXPORT_SYMBOL_GPL(platform_device_register);
 782
 783/**
 784 * platform_device_unregister - unregister a platform-level device
 785 * @pdev: platform device we're unregistering
 786 *
 787 * Unregistration is done in 2 steps. First we release all resources
 788 * and remove it from the subsystem, then we drop reference count by
 789 * calling platform_device_put().
 790 */
 791void platform_device_unregister(struct platform_device *pdev)
 792{
 793	platform_device_del(pdev);
 794	platform_device_put(pdev);
 795}
 796EXPORT_SYMBOL_GPL(platform_device_unregister);
 797
 798/**
 799 * platform_device_register_full - add a platform-level device with
 800 * resources and platform-specific data
 801 *
 802 * @pdevinfo: data used to create device
 803 *
 804 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
 805 */
 806struct platform_device *platform_device_register_full(
 807		const struct platform_device_info *pdevinfo)
 808{
 809	int ret;
 810	struct platform_device *pdev;
 811
 812	pdev = platform_device_alloc(pdevinfo->name, pdevinfo->id);
 813	if (!pdev)
 814		return ERR_PTR(-ENOMEM);
 815
 816	pdev->dev.parent = pdevinfo->parent;
 817	pdev->dev.fwnode = pdevinfo->fwnode;
 818	pdev->dev.of_node = of_node_get(to_of_node(pdev->dev.fwnode));
 819	pdev->dev.of_node_reused = pdevinfo->of_node_reused;
 820
 821	if (pdevinfo->dma_mask) {
 822		pdev->platform_dma_mask = pdevinfo->dma_mask;
 823		pdev->dev.dma_mask = &pdev->platform_dma_mask;
 
 
 
 
 
 
 
 
 
 
 824		pdev->dev.coherent_dma_mask = pdevinfo->dma_mask;
 825	}
 826
 827	ret = platform_device_add_resources(pdev,
 828			pdevinfo->res, pdevinfo->num_res);
 829	if (ret)
 830		goto err;
 831
 832	ret = platform_device_add_data(pdev,
 833			pdevinfo->data, pdevinfo->size_data);
 834	if (ret)
 835		goto err;
 836
 837	if (pdevinfo->properties) {
 838		ret = device_create_managed_software_node(&pdev->dev,
 839							  pdevinfo->properties, NULL);
 840		if (ret)
 841			goto err;
 842	}
 843
 844	ret = platform_device_add(pdev);
 845	if (ret) {
 846err:
 847		ACPI_COMPANION_SET(&pdev->dev, NULL);
 
 
 
 848		platform_device_put(pdev);
 849		return ERR_PTR(ret);
 850	}
 851
 852	return pdev;
 853}
 854EXPORT_SYMBOL_GPL(platform_device_register_full);
 855
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 856/**
 857 * __platform_driver_register - register a driver for platform-level devices
 858 * @drv: platform driver structure
 859 * @owner: owning module/driver
 860 */
 861int __platform_driver_register(struct platform_driver *drv,
 862				struct module *owner)
 863{
 864	drv->driver.owner = owner;
 865	drv->driver.bus = &platform_bus_type;
 
 
 
 
 
 
 866
 867	return driver_register(&drv->driver);
 868}
 869EXPORT_SYMBOL_GPL(__platform_driver_register);
 870
 871/**
 872 * platform_driver_unregister - unregister a driver for platform-level devices
 873 * @drv: platform driver structure
 874 */
 875void platform_driver_unregister(struct platform_driver *drv)
 876{
 877	driver_unregister(&drv->driver);
 878}
 879EXPORT_SYMBOL_GPL(platform_driver_unregister);
 880
 881static int platform_probe_fail(struct platform_device *pdev)
 882{
 883	return -ENXIO;
 884}
 885
 886/**
 887 * __platform_driver_probe - register driver for non-hotpluggable device
 888 * @drv: platform driver structure
 889 * @probe: the driver probe routine, probably from an __init section
 890 * @module: module which will be the owner of the driver
 891 *
 892 * Use this instead of platform_driver_register() when you know the device
 893 * is not hotpluggable and has already been registered, and you want to
 894 * remove its run-once probe() infrastructure from memory after the driver
 895 * has bound to the device.
 896 *
 897 * One typical use for this would be with drivers for controllers integrated
 898 * into system-on-chip processors, where the controller devices have been
 899 * configured as part of board setup.
 900 *
 901 * Note that this is incompatible with deferred probing.
 902 *
 903 * Returns zero if the driver registered and bound to a device, else returns
 904 * a negative error code and with the driver not registered.
 905 */
 906int __init_or_module __platform_driver_probe(struct platform_driver *drv,
 907		int (*probe)(struct platform_device *), struct module *module)
 908{
 909	int retval, code;
 910
 911	if (drv->driver.probe_type == PROBE_PREFER_ASYNCHRONOUS) {
 912		pr_err("%s: drivers registered with %s can not be probed asynchronously\n",
 913			 drv->driver.name, __func__);
 914		return -EINVAL;
 915	}
 916
 917	/*
 918	 * We have to run our probes synchronously because we check if
 919	 * we find any devices to bind to and exit with error if there
 920	 * are any.
 921	 */
 922	drv->driver.probe_type = PROBE_FORCE_SYNCHRONOUS;
 923
 924	/*
 925	 * Prevent driver from requesting probe deferral to avoid further
 926	 * futile probe attempts.
 927	 */
 928	drv->prevent_deferred_probe = true;
 929
 930	/* make sure driver won't have bind/unbind attributes */
 931	drv->driver.suppress_bind_attrs = true;
 932
 933	/* temporary section violation during probe() */
 934	drv->probe = probe;
 935	retval = code = __platform_driver_register(drv, module);
 936	if (retval)
 937		return retval;
 938
 939	/*
 940	 * Fixup that section violation, being paranoid about code scanning
 941	 * the list of drivers in order to probe new devices.  Check to see
 942	 * if the probe was successful, and make sure any forced probes of
 943	 * new devices fail.
 944	 */
 945	spin_lock(&drv->driver.bus->p->klist_drivers.k_lock);
 946	drv->probe = platform_probe_fail;
 947	if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
 948		retval = -ENODEV;
 
 949	spin_unlock(&drv->driver.bus->p->klist_drivers.k_lock);
 950
 951	if (code != retval)
 952		platform_driver_unregister(drv);
 953	return retval;
 954}
 955EXPORT_SYMBOL_GPL(__platform_driver_probe);
 956
 957/**
 958 * __platform_create_bundle - register driver and create corresponding device
 959 * @driver: platform driver structure
 960 * @probe: the driver probe routine, probably from an __init section
 961 * @res: set of resources that needs to be allocated for the device
 962 * @n_res: number of resources
 963 * @data: platform specific data for this platform device
 964 * @size: size of platform specific data
 965 * @module: module which will be the owner of the driver
 966 *
 967 * Use this in legacy-style modules that probe hardware directly and
 968 * register a single platform device and corresponding platform driver.
 969 *
 970 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
 971 */
 972struct platform_device * __init_or_module __platform_create_bundle(
 973			struct platform_driver *driver,
 974			int (*probe)(struct platform_device *),
 975			struct resource *res, unsigned int n_res,
 976			const void *data, size_t size, struct module *module)
 977{
 978	struct platform_device *pdev;
 979	int error;
 980
 981	pdev = platform_device_alloc(driver->driver.name, -1);
 982	if (!pdev) {
 983		error = -ENOMEM;
 984		goto err_out;
 985	}
 986
 987	error = platform_device_add_resources(pdev, res, n_res);
 988	if (error)
 989		goto err_pdev_put;
 990
 991	error = platform_device_add_data(pdev, data, size);
 992	if (error)
 993		goto err_pdev_put;
 994
 995	error = platform_device_add(pdev);
 996	if (error)
 997		goto err_pdev_put;
 998
 999	error = __platform_driver_probe(driver, probe, module);
1000	if (error)
1001		goto err_pdev_del;
1002
1003	return pdev;
1004
1005err_pdev_del:
1006	platform_device_del(pdev);
1007err_pdev_put:
1008	platform_device_put(pdev);
1009err_out:
1010	return ERR_PTR(error);
1011}
1012EXPORT_SYMBOL_GPL(__platform_create_bundle);
1013
1014/**
1015 * __platform_register_drivers - register an array of platform drivers
1016 * @drivers: an array of drivers to register
1017 * @count: the number of drivers to register
1018 * @owner: module owning the drivers
1019 *
1020 * Registers platform drivers specified by an array. On failure to register a
1021 * driver, all previously registered drivers will be unregistered. Callers of
1022 * this API should use platform_unregister_drivers() to unregister drivers in
1023 * the reverse order.
1024 *
1025 * Returns: 0 on success or a negative error code on failure.
1026 */
1027int __platform_register_drivers(struct platform_driver * const *drivers,
1028				unsigned int count, struct module *owner)
1029{
1030	unsigned int i;
1031	int err;
1032
1033	for (i = 0; i < count; i++) {
1034		pr_debug("registering platform driver %ps\n", drivers[i]);
 
1035
1036		err = __platform_driver_register(drivers[i], owner);
1037		if (err < 0) {
1038			pr_err("failed to register platform driver %ps: %d\n",
1039			       drivers[i], err);
1040			goto error;
1041		}
1042	}
1043
1044	return 0;
1045
1046error:
1047	while (i--) {
1048		pr_debug("unregistering platform driver %ps\n", drivers[i]);
1049		platform_driver_unregister(drivers[i]);
1050	}
1051
1052	return err;
1053}
1054EXPORT_SYMBOL_GPL(__platform_register_drivers);
 
 
1055
1056/**
1057 * platform_unregister_drivers - unregister an array of platform drivers
1058 * @drivers: an array of drivers to unregister
1059 * @count: the number of drivers to unregister
1060 *
1061 * Unregisters platform drivers specified by an array. This is typically used
1062 * to complement an earlier call to platform_register_drivers(). Drivers are
1063 * unregistered in the reverse order in which they were registered.
1064 */
1065void platform_unregister_drivers(struct platform_driver * const *drivers,
1066				 unsigned int count)
1067{
1068	while (count--) {
1069		pr_debug("unregistering platform driver %ps\n", drivers[count]);
1070		platform_driver_unregister(drivers[count]);
1071	}
 
 
 
 
 
 
 
 
 
 
 
1072}
1073EXPORT_SYMBOL_GPL(platform_unregister_drivers);
1074
1075static const struct platform_device_id *platform_match_id(
1076			const struct platform_device_id *id,
1077			struct platform_device *pdev)
1078{
1079	while (id->name[0]) {
1080		if (strcmp(pdev->name, id->name) == 0) {
1081			pdev->id_entry = id;
1082			return id;
1083		}
1084		id++;
1085	}
1086	return NULL;
1087}
1088
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1089#ifdef CONFIG_PM_SLEEP
1090
1091static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
1092{
1093	struct platform_driver *pdrv = to_platform_driver(dev->driver);
1094	struct platform_device *pdev = to_platform_device(dev);
1095	int ret = 0;
1096
1097	if (dev->driver && pdrv->suspend)
1098		ret = pdrv->suspend(pdev, mesg);
1099
1100	return ret;
1101}
1102
1103static int platform_legacy_resume(struct device *dev)
1104{
1105	struct platform_driver *pdrv = to_platform_driver(dev->driver);
1106	struct platform_device *pdev = to_platform_device(dev);
1107	int ret = 0;
1108
1109	if (dev->driver && pdrv->resume)
1110		ret = pdrv->resume(pdev);
1111
1112	return ret;
1113}
1114
1115#endif /* CONFIG_PM_SLEEP */
1116
1117#ifdef CONFIG_SUSPEND
1118
1119int platform_pm_suspend(struct device *dev)
1120{
1121	struct device_driver *drv = dev->driver;
1122	int ret = 0;
1123
1124	if (!drv)
1125		return 0;
1126
1127	if (drv->pm) {
1128		if (drv->pm->suspend)
1129			ret = drv->pm->suspend(dev);
1130	} else {
1131		ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
1132	}
1133
1134	return ret;
1135}
1136
1137int platform_pm_resume(struct device *dev)
1138{
1139	struct device_driver *drv = dev->driver;
1140	int ret = 0;
1141
1142	if (!drv)
1143		return 0;
1144
1145	if (drv->pm) {
1146		if (drv->pm->resume)
1147			ret = drv->pm->resume(dev);
1148	} else {
1149		ret = platform_legacy_resume(dev);
1150	}
1151
1152	return ret;
1153}
1154
1155#endif /* CONFIG_SUSPEND */
1156
1157#ifdef CONFIG_HIBERNATE_CALLBACKS
1158
1159int platform_pm_freeze(struct device *dev)
1160{
1161	struct device_driver *drv = dev->driver;
1162	int ret = 0;
1163
1164	if (!drv)
1165		return 0;
1166
1167	if (drv->pm) {
1168		if (drv->pm->freeze)
1169			ret = drv->pm->freeze(dev);
1170	} else {
1171		ret = platform_legacy_suspend(dev, PMSG_FREEZE);
1172	}
1173
1174	return ret;
1175}
1176
1177int platform_pm_thaw(struct device *dev)
1178{
1179	struct device_driver *drv = dev->driver;
1180	int ret = 0;
1181
1182	if (!drv)
1183		return 0;
1184
1185	if (drv->pm) {
1186		if (drv->pm->thaw)
1187			ret = drv->pm->thaw(dev);
1188	} else {
1189		ret = platform_legacy_resume(dev);
1190	}
1191
1192	return ret;
1193}
1194
1195int platform_pm_poweroff(struct device *dev)
1196{
1197	struct device_driver *drv = dev->driver;
1198	int ret = 0;
1199
1200	if (!drv)
1201		return 0;
1202
1203	if (drv->pm) {
1204		if (drv->pm->poweroff)
1205			ret = drv->pm->poweroff(dev);
1206	} else {
1207		ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
1208	}
1209
1210	return ret;
1211}
1212
1213int platform_pm_restore(struct device *dev)
1214{
1215	struct device_driver *drv = dev->driver;
1216	int ret = 0;
1217
1218	if (!drv)
1219		return 0;
1220
1221	if (drv->pm) {
1222		if (drv->pm->restore)
1223			ret = drv->pm->restore(dev);
1224	} else {
1225		ret = platform_legacy_resume(dev);
1226	}
1227
1228	return ret;
1229}
1230
1231#endif /* CONFIG_HIBERNATE_CALLBACKS */
1232
1233/* modalias support enables more hands-off userspace setup:
1234 * (a) environment variable lets new-style hotplug events work once system is
1235 *     fully running:  "modprobe $MODALIAS"
1236 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
1237 *     mishandled before system is fully running:  "modprobe $(cat modalias)"
1238 */
1239static ssize_t modalias_show(struct device *dev,
1240			     struct device_attribute *attr, char *buf)
1241{
1242	struct platform_device *pdev = to_platform_device(dev);
1243	int len;
1244
1245	len = of_device_modalias(dev, buf, PAGE_SIZE);
1246	if (len != -ENODEV)
1247		return len;
 
 
 
 
 
1248
1249	len = acpi_device_modalias(dev, buf, PAGE_SIZE - 1);
1250	if (len != -ENODEV)
1251		return len;
1252
1253	return sysfs_emit(buf, "platform:%s\n", pdev->name);
1254}
1255static DEVICE_ATTR_RO(modalias);
1256
1257static ssize_t numa_node_show(struct device *dev,
1258			      struct device_attribute *attr, char *buf)
1259{
1260	return sysfs_emit(buf, "%d\n", dev_to_node(dev));
1261}
1262static DEVICE_ATTR_RO(numa_node);
1263
1264static ssize_t driver_override_show(struct device *dev,
1265				    struct device_attribute *attr, char *buf)
1266{
1267	struct platform_device *pdev = to_platform_device(dev);
1268	ssize_t len;
1269
1270	device_lock(dev);
1271	len = sysfs_emit(buf, "%s\n", pdev->driver_override);
1272	device_unlock(dev);
1273
1274	return len;
 
 
1275}
1276
1277static ssize_t driver_override_store(struct device *dev,
1278				     struct device_attribute *attr,
1279				     const char *buf, size_t count)
1280{
1281	struct platform_device *pdev = to_platform_device(dev);
1282	int ret;
1283
1284	ret = driver_set_override(dev, &pdev->driver_override, buf, count);
1285	if (ret)
1286		return ret;
1287
1288	return count;
 
 
 
 
 
 
 
1289}
1290static DEVICE_ATTR_RW(driver_override);
1291
1292static struct attribute *platform_dev_attrs[] = {
1293	&dev_attr_modalias.attr,
1294	&dev_attr_numa_node.attr,
1295	&dev_attr_driver_override.attr,
1296	NULL,
1297};
1298
1299static umode_t platform_dev_attrs_visible(struct kobject *kobj, struct attribute *a,
1300		int n)
1301{
1302	struct device *dev = container_of(kobj, typeof(*dev), kobj);
1303
1304	if (a == &dev_attr_numa_node.attr &&
1305			dev_to_node(dev) == NUMA_NO_NODE)
1306		return 0;
1307
1308	return a->mode;
1309}
1310
1311static const struct attribute_group platform_dev_group = {
1312	.attrs = platform_dev_attrs,
1313	.is_visible = platform_dev_attrs_visible,
1314};
1315__ATTRIBUTE_GROUPS(platform_dev);
1316
 
 
1317
1318/**
1319 * platform_match - bind platform device to platform driver.
1320 * @dev: device.
1321 * @drv: driver.
1322 *
1323 * Platform device IDs are assumed to be encoded like this:
1324 * "<name><instance>", where <name> is a short description of the type of
1325 * device, like "pci" or "floppy", and <instance> is the enumerated
1326 * instance of the device, like '0' or '42'.  Driver IDs are simply
1327 * "<name>".  So, extract the <name> from the platform_device structure,
1328 * and compare it against the name of the driver. Return whether they match
1329 * or not.
1330 */
1331static int platform_match(struct device *dev, struct device_driver *drv)
 
1332{
1333	struct platform_device *pdev = to_platform_device(dev);
1334	struct platform_driver *pdrv = to_platform_driver(drv);
1335
1336	/* When driver_override is set, only bind to the matching driver */
1337	if (pdev->driver_override)
1338		return !strcmp(pdev->driver_override, drv->name);
 
 
 
 
1339
1340	/* Attempt an OF style match first */
1341	if (of_driver_match_device(dev, drv))
1342		return 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1343
1344	/* Then try ACPI style match */
1345	if (acpi_driver_match_device(dev, drv))
1346		return 1;
1347
1348	/* Then try to match against the id table */
1349	if (pdrv->id_table)
1350		return platform_match_id(pdrv->id_table, pdev) != NULL;
 
 
 
1351
1352	/* fall-back to driver name match */
1353	return (strcmp(pdev->name, drv->name) == 0);
1354}
1355
1356static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
 
 
 
 
 
 
 
 
1357{
1358	struct platform_device	*pdev = to_platform_device(dev);
1359	int rc;
1360
1361	/* Some devices have extra OF data and an OF-style MODALIAS */
1362	rc = of_device_uevent_modalias(dev, env);
1363	if (rc != -ENODEV)
1364		return rc;
1365
1366	rc = acpi_device_uevent_modalias(dev, env);
1367	if (rc != -ENODEV)
1368		return rc;
 
 
 
 
 
1369
1370	add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
1371			pdev->name);
1372	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1373}
1374
1375static int platform_probe(struct device *_dev)
 
 
 
 
 
 
1376{
1377	struct platform_driver *drv = to_platform_driver(_dev->driver);
1378	struct platform_device *dev = to_platform_device(_dev);
1379	int ret;
1380
1381	/*
1382	 * A driver registered using platform_driver_probe() cannot be bound
1383	 * again later because the probe function usually lives in __init code
1384	 * and so is gone. For these drivers .probe is set to
1385	 * platform_probe_fail in __platform_driver_probe(). Don't even prepare
1386	 * clocks and PM domains for these to match the traditional behaviour.
1387	 */
1388	if (unlikely(drv->probe == platform_probe_fail))
1389		return -ENXIO;
1390
1391	ret = of_clk_set_defaults(_dev->of_node, false);
1392	if (ret < 0)
1393		return ret;
1394
1395	ret = dev_pm_domain_attach(_dev, true);
1396	if (ret)
1397		goto out;
 
 
 
 
 
 
 
 
 
 
 
1398
1399	if (drv->probe) {
1400		ret = drv->probe(dev);
1401		if (ret)
1402			dev_pm_domain_detach(_dev, true);
1403	}
1404
1405out:
1406	if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
1407		dev_warn(_dev, "probe deferral not supported\n");
1408		ret = -ENXIO;
1409	}
1410
1411	return ret;
1412}
1413
1414static void platform_remove(struct device *_dev)
1415{
1416	struct platform_driver *drv = to_platform_driver(_dev->driver);
1417	struct platform_device *dev = to_platform_device(_dev);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1418
1419	if (drv->remove) {
1420		int ret = drv->remove(dev);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1421
1422		if (ret)
1423			dev_warn(_dev, "remove callback returned a non-zero value. This will be ignored.\n");
1424	}
1425	dev_pm_domain_detach(_dev, true);
1426}
 
 
 
 
 
 
1427
1428static void platform_shutdown(struct device *_dev)
1429{
1430	struct platform_device *dev = to_platform_device(_dev);
1431	struct platform_driver *drv;
 
 
 
 
 
 
 
 
 
 
 
 
1432
1433	if (!_dev->driver)
1434		return;
 
1435
1436	drv = to_platform_driver(_dev->driver);
1437	if (drv->shutdown)
1438		drv->shutdown(dev);
1439}
 
 
1440
1441static int platform_dma_configure(struct device *dev)
1442{
1443	struct platform_driver *drv = to_platform_driver(dev->driver);
1444	enum dev_dma_attr attr;
1445	int ret = 0;
1446
1447	if (dev->of_node) {
1448		ret = of_dma_configure(dev, dev->of_node, true);
1449	} else if (has_acpi_companion(dev)) {
1450		attr = acpi_get_dma_attr(to_acpi_device_node(dev->fwnode));
1451		ret = acpi_dma_configure(dev, attr);
1452	}
1453
1454	if (!ret && !drv->driver_managed_dma) {
1455		ret = iommu_device_use_default_domain(dev);
1456		if (ret)
1457			arch_teardown_dma_ops(dev);
1458	}
1459
1460	return ret;
 
 
 
1461}
1462
1463static void platform_dma_cleanup(struct device *dev)
 
 
 
 
 
 
 
 
 
 
 
 
1464{
1465	struct platform_driver *drv = to_platform_driver(dev->driver);
1466
1467	if (!drv->driver_managed_dma)
1468		iommu_device_unuse_default_domain(dev);
1469}
 
 
 
1470
1471static const struct dev_pm_ops platform_dev_pm_ops = {
1472	SET_RUNTIME_PM_OPS(pm_generic_runtime_suspend, pm_generic_runtime_resume, NULL)
1473	USE_PLATFORM_PM_SLEEP_OPS
1474};
1475
1476struct bus_type platform_bus_type = {
1477	.name		= "platform",
1478	.dev_groups	= platform_dev_groups,
1479	.match		= platform_match,
1480	.uevent		= platform_uevent,
1481	.probe		= platform_probe,
1482	.remove		= platform_remove,
1483	.shutdown	= platform_shutdown,
1484	.dma_configure	= platform_dma_configure,
1485	.dma_cleanup	= platform_dma_cleanup,
1486	.pm		= &platform_dev_pm_ops,
1487};
1488EXPORT_SYMBOL_GPL(platform_bus_type);
1489
1490static inline int __platform_match(struct device *dev, const void *drv)
1491{
1492	return platform_match(dev, (struct device_driver *)drv);
1493}
1494
1495/**
1496 * platform_find_device_by_driver - Find a platform device with a given
1497 * driver.
1498 * @start: The device to start the search from.
1499 * @drv: The device driver to look for.
1500 */
1501struct device *platform_find_device_by_driver(struct device *start,
1502					      const struct device_driver *drv)
1503{
1504	return bus_find_device(&platform_bus_type, start, drv,
1505			       __platform_match);
1506}
1507EXPORT_SYMBOL_GPL(platform_find_device_by_driver);
1508
1509void __weak __init early_platform_cleanup(void) { }
1510
1511int __init platform_bus_init(void)
1512{
1513	int error;
1514
1515	early_platform_cleanup();
1516
1517	error = device_register(&platform_bus);
1518	if (error) {
1519		put_device(&platform_bus);
1520		return error;
 
1521	}
1522	error =  bus_register(&platform_bus_type);
1523	if (error)
1524		device_unregister(&platform_bus);
1525	of_platform_register_reconfig_notifier();
1526	return error;
1527}